SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'efc5daf11ba9a9933d2c7b3cab6d530a62c48c1521c867c66466a613d6f5536c' 
  AND token = 'MdnOOC4u/QAk/lMQvJhqQFkQzyeV5G98R873dbbox94=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}